The present invention relates to methods of making total parenteral nutrition (TPN) solutions. More particularly, the step-wise procedure for making TPN solutions which is disclosed herein guarantees that the solutions conform to acceptable standards of repeatability and physiologic compatibility. This method of forming TPN solutions is easily adapted to computerized control.
In the last few years, there has been a rapid expansion in the use of TPN solutions to treat hospitalized patients. In part, this expansion of TPN usage has been fueled by a series of discoveries which are leading to an optimization of TPN solutions for treatment of particular conditions. Nowhere is this more apparent than in the modification of the content of the fats used in TPN solutions. The traditional soybean or safflower oil used to provide the lipid content to TPN solutions is now being replaced, at least in part, by a variety of different lipids. These include omega-3 fatty acids (U.S. Pat. Nos. 4,752,618 and 4,871,731, both assigned to New England Deaconess Hospital Corporation), medium-chain triglycerides or MCT's (U.S. Pat. No. 4,528,197, assigned to KabiVitrum), structured lipids having both MCT and Omega-3 fatty acids on the same backbone (U.S. Pat. No. 4,871,768, assigned to New England Deaconess Hospital Corporation), kernel oils (U.S. Pat. No. 4,810,726, assigned to New England Deaconess Hospital Corporation), structured lipids containing dairy fats (U.S. Pat. No. 4,952,606, assigned to New England Deaconess Hospital Corporation), and structured lipids containing short-chain fatty acids (PCT Publication No. W090/12080, assigned to New England Deaconess Hospital Corporation). In addition, even the structure of the amino acids used in the parenteral nutrition solution have been modified. For certain uses, branched chain amino acids are preferable to straight chain amino acids (U.S. Pat. No. 4,438,144, assigned to Baxter Travenol Laboratories).
The rapid explosion of information concerning TPN solutions and what modifications must be made to the solutions when using each different type of fats and amino acids to achieve optimum results has made it particularly difficult for pharmacists and physicians to make sure the solutions are produced accurately. In addition, as more and different types of drugs are being delivered in conjunction with TPN solutions, determining compatibility of the drugs and a variety of ionic materials is more difficult for the physician and/or pharmacist ordering or formulating the TPN solution. Another factor which must be monitored is whether the various ionic materials affect the strength and stability of the lipid carrying emulsion itself. For example, if the concentration of ionic materials is too great or of the wrong type, the emulsion in the TPN solution may be destabilized or break down. Still another problem is making sure that the cumulative amounts of ions, drugs and other ingredients of the TPN solutions are monitored so that they do not exceed predetermined safety limits nor adversely affect the osmoticity of the solution. Similarly, the intravenous set used for delivery of the TPN solution must be of proper type for the particular TPN solution and it be changed, when necessary, because of any differences made in the TPN solution for a particular patient
Accordingly, an object to the invention is to provide a method of preparing TPN solutions in a controlled manner such that there are no adverse drug or ionic interactions or emulsion destabilizing problems.
Another object to the invention is to provide a method of preparing TPN solutions so that mistakes which could be injurious to the patient by a pharmacist or physician are minimized.
A further object to the invention is to provide a computer control system for the manufacture of TPN solutions.
These and other objects and features of the invention will be apparent from the following detailed description.